The Developmental Processes in Schizophrenic Disorders project involves an ongoing, longitudinal, follow-through study of schizophrenic patients whose psychosis has had a recent onset. The project focuses on the predictive role for relapse and course of illness played by certain personal vulnerability factors and environmental potentiating factors, first under standardized antipsychotic medication conditions and later during withdrawal of medication. A parallel aim is to identify and discriminate variables that are "stable vulnerability indicators," "mediating vulnerability factors," and "episode indicators" in relationship to schizophrenic symptoms. In addition to comparisons to a normal sample, the project seeks to examine the specificity of these relationships with schizophrenic symptoms by comparison to relationships with manic symptoms in a group with bipolar affective disorder. The intra-individual areas that are assessed include symptomatology, attentional functioning and information processing, psychophysiology, social behavior, and antipsychotic blood levels. Assessments of possible environmental potentiating factors are completed in the areas of family attitudes and behavior, the patient's social network, and stressful life events. Family history of schizophrenia and related psychiatric disorders will also be assessed to examine its predictive role and relationship to certain personal vulnerability factors. The first phase of the project involves a one-year outpatient follow-through design with repeated measurement while the schizophrenic patients are maintained on a standardized dosage of antipsychotic medication. The second phase involves the continuation of the study of the recent-onset schizophrenic sample during the second and third post-discharge years. During this second period, the effects of antipsychotic-medication/placebo crossover are examined for 24 weeks, followed by an 18-month antipsychotic medication withdrawal period for all patients showing no adverse effects during the placebo period.